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61.
Persistent organic pollutants (POPs) are ubiquitous residual contaminants in the environment and in the food chain. Milk is an important matrix for monitoring POP contamination. This study determined the concentrations of POPs including polybrominated diphenyl ethers (PBDEs), hexachlorobenzene (HCB), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and dioxin-like polychlorinated biphenyls (DL-PCBs) in raw bovine milk, and the data was used to estimate dietary intakes in South Korea. The average concentrations of PBDEs, HCB, PCDD/Fs, and DL-PCBs in raw milk were 0.29 ng g−1 fat, 0.50 ng g−1 fat, 0.27 pg TEQ g−1 fat, and 0.33 pg TEQ g−1 fat, respectively. No significant relationship was found between the concentrations of analytes and the regions sampled. The dietary intakes of PBDEs from the consumption of milk was calculated to be 0.26, 0.10, and 0.05 ng kg−1 bw d−1 for the group of ages 0–6, 7–12, and 13–19, respectively. The dietary intakes of HCB was calculated to be 0.44, 0.16, and 0.09 ng kg−1 bw d−1 for the group of ages 0–6, 7–12, and 13–19, respectively. The dietary intakes of PCDD/Fs and DL-PCBs was calculated to be 0.78, 0.29, and 0.16 pg TEQ kg−1 bw d−1 for the group of ages 0–6, 7–12, and 13–19, respectively. These results indicated that the residual levels of PBDEs, HCB, PCDD/Fs, and DL-PCBs in raw bovine milk were within safe levels.  相似文献   
62.
The aim of the Bavarian Monitoring of Breast Milk (BAMBI) project was to examine 10 organochlorine pesticides (OPs), 3 nitro musks, 6 indicator polychlorinated biphenyls (PCBs), 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), 12 dioxin-like PCBs (dl-PCBs) and several perfluorinated alkyl compounds in breast milk samples. A total of 516 breast milk samples were collected from seven regions in Bavaria and were analyzed by means of GC/ECD, GC/HRMS, and LC/MS-MS.  相似文献   
63.
The objective of this study was to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) in cow's milk from industrial farms that are located near an industrial park in Hidalgo, Mexico. It was found that the concentrations of PAHs in the raw milk of cattle from industrial farms have increased in recent years. Composite samples were collected between 2008 and 2010 and analysis carried out according to 8100 EPA procedures and analyzed by gas chromatography with FID detection. The results show that combustion PAHs were mostly Ace, Acy, and Fla (0.25, 0.32, and 0.22 µg g?1, respectively). Diagnostic ratios were used to show that the probable sources were grass and fuel combustion. The sum of concentrations of 16 individual PAHs did not breach permissible levels in milk (25 µg g?1 according to the United States EPA), indicating a limited health risk to animals and humans in the study area. The industrial park has adequate pollutant emission regulations.  相似文献   
64.
紫云英是豫南稻区土壤培肥的重要有机肥资源,探究紫云英还田与化肥减量配施对稻田土壤理化性质和细菌群落特性的影响,旨在为该区域的土壤培肥和化肥减量提供依据.开展连续12 a田间定位试验,设置了6个施肥处理(空白对照,CK;单施化肥,F100;80%化肥和22.5t·hm-2紫云英还田量配施,MV1F80;80%化肥和45 t·hm-2紫云英还田量配施,MV2F80;60%化肥和22.5 t·hm-2紫云英还田量配施,MV1F60;60%化肥和45 t·hm-2紫云英还田量配施,MV2F60).通过采用高通量测序方法比较不同施肥处理对土壤细菌群落多样性、组成和结构特性的影响;采用FAPROTAX功能预测的方法分析不同施肥处理间功能类群的丰度差异,并结合土壤理化性质,探究改变土壤细菌群落结构与功能特性的关键土壤环境因子.结果表明,紫云英还田与化肥减量配施降低了土壤容重,提高了土壤有机碳(SOC)、全氮(TN)、全磷(TP)和全钾(TK)含量,较CK提高的范围分别为12.7%~35.5%、38.2%~65.7...  相似文献   
65.
准确评估种养一体化奶牛场的经济性能与环境绩效,是相关支持政策制定的基础,也是促进奶业低碳生产的关键.本文基于生命周期视角,对非种养一体化奶牛场(non-IPBS)和种养一体化奶牛场(IPBS)养殖过程中的温室气体排放、能源消耗、水消耗、土地占用等环境成本和经济效益进行评估.结果表明,non-IPBS生产1t标准牛奶(FPCM)的净收益为1427元,而IPBS的实际净收益提高7%,如果青贮玉米自给率从当前的32%提升到100%,则实际净收益将提高19%,同时,该净收益的提高率取决于耕地流转费用,临界点为14695元/hm2;相比non-IPBS,IPBS生产1tFPCM的温室气体排放、能源消耗、水消耗、土地占用分别减少6%、6%、5%、7%,如果青贮玉米自给率提升到100%,则相应减少16%、16%、11%、14%.IPBS在降低青贮玉米种植的化肥施用、解决养殖场粪便污染等方面优势明显,在提升养殖经济效益、降低温室气体排放等方面具有巨大潜力,值得推广.  相似文献   
66.
The concept of sustainable development is forcing standard economic analysis to acknowledge and address the existence of dimensions of performance, which are not reducible to monetary accounting. In particular, the implementation of this concept in practice requires: (a) the simultaneous handling of indicators developed in different disciplinary fields; and (b) an approach more related to the procedures adopted by consultants (Participatory Integrated Analysis), rather than theoretical academic analysis looking for ‘the’ optimal solution. The case study considered in this paper is a multi-criteria analysis of changes, which occurred in the Swedish milk production sector for the period 1989–1999. Multi-criteria impact matrices and multi-criteria representations are used to provide a transparent method of integrated analysis. Changes are characterized and quantified in a way that makes it possible to relate the impact of existing trends in relation to different sub-objectives (variation in performance in relation to social, economic and ecological indicators). The results of this analysis confirm a few well known predicaments of sustainability associated with agriculture. The growth of Sweden economy is driving a major increase in material throughputs within its agricultural sector. The need of increasing agricultural throughput (especially labour productivity) has moved the Swedish dairy sector in a clear situation of decreasing marginal return ( = large increases in inputs are not reflected in a proportional increase in output). Therefore, sound policies of development of this sector aimed at increasing the goal of sustainability have to be developed by considering several indicators of performance, and not only economic variables.  相似文献   
67.
Polybrominated diphenyl ethers(PBDEs) can be transferred to infants through the ingestion of breast milk, resulting in potential health risk. In this study, PBDEs, hydroxylated polybrominated diphenyl ethers(OH-PBDEs) and 2,2′,4,4′,5,6′-hexachlorobiphenyl(CB-153)in human milk from women living adjacent to e-waste recycling sites of Wenling,China, were investigated. The median level of PBDEs in samples from residents living in the e-waste recycling environment 20 years(R_20group, 19.5 ng/g lipid weight(lw))was significantly higher than that for residents living in Wenling 3 years(R_3group,3.88 ng/g lw)(p 0.05), likely ascribable to specific exposure to PBDEs from e-waste recycling activities. In the R_20 group, most congeners(except for BDE-209) were correlated with each other(p 0.05). Moreover, CB-153 showed significant association with most PBDE congeners, rather than BDE-209. The relationship indicated that most BDE congeners other than BDE-209 shared common sources and/or pathways with CB-153, e.g., dietary ingestion. The correlations between BDE-209 and other congeners were different in the two groups, likely suggesting their different exposure sources and/or pathways for PBDEs.Although estimated dietary intake of PBDEs for infants via breast milk was lower than the minimum value affecting human health, the PBDE exposure of infants should be of great concern because of their potential effect on the development of neonates over long-term exposure. OH-PBDEs were not detected in the collected samples, which is in accordance with reports in published literature, likely indicating that they were not apt to be accumulated in human milk.  相似文献   
68.
周泉  王龙昌  熊瑛  张赛  杜娟  赵琳璐 《环境科学》2016,37(3):1114-1120
在全球变暖的大背景下,农田土壤呼吸成为农业碳排放的主要途径,而绿肥对抑制温室气体排放、实现节能减排有巨大潜力.在我国西南紫色土地区,有关绿肥间作条件下的农田土壤呼吸特征尚不明确.通过绿肥紫云英与油菜间作,重点研究了秸秆覆盖条件下紫云英与油菜间作对冬季油菜根际土壤有机碳及土壤呼吸的影响.结果表明,与秸秆覆盖相比,隔根方式成为影响油菜根际土壤有机碳含量的主要因素,绿肥间作使油菜根际土壤有机碳含量显著降低;秸秆覆盖可促进油菜田间土壤呼吸,而绿肥间作抑制了油菜田间土壤呼吸,土壤呼吸受油菜生育阶段影响较大,呈现出先下降后升高再下降的总体特征,且与土壤温度之间表现出回归式抛物线关系,根际呼吸在油菜生长后期成为土壤呼吸的主要成分.  相似文献   
69.
The objective of this study was to produce a generic monoclonal antibody for multi-determination of the residues of tetracycline drugs in bovine muscle and milk. Two new immunogens of doxycycline were prepared that were used to produce the monoclonal antibodies. Results showed the obtained antibodies simultaneously recognized seven tetracycline drugs (doxycycline, tetracycline, chlortetracycline, oxytetracycline, minocycline, methacycline, demeclocycline). The obtained antibodies and three coating antigens were arranged into six combinations to optimize the reagents combination. After comparison of the performances of these combinations, a heterologous indirect competitive ELISA was then used to determine the seven tetracyclines in bovine muscle and milk. The crossreactivities to the seven analytes were in the range of 47%–102% and the limits of detection were in the range of 1.5–6.9 ng/mL depending on the compound. The recoveries of the seven drugs from fortified blank samples were in the range of 75.3%–106.8% with coefficients of variation lower than 10.9%. Therefore, this method could be used as a multi-analytes screen tool for routine monitoring of the residues of these tetracycline drugs in bovine muscle and milk.  相似文献   
70.
Abstract

This paper describes a simple, inexpensive, highly sensitive, selective, and efficient electrochemical method to determine glyphosate (GLY) in samples of milk, orange juice, and agricultural formulation. The oxidation reaction on the electrode surface was electrochemically characterised by cyclic voltammetry (CV) and square wave voltammetry (SWV). The investigation of GLY at carbon paste electrode revealed a non-reversible oxidation peak at +0.95 V versus Ag/AgCl, which was used for electrochemical detection of GLY. The operating parameters (pH, frequency, step potential, and amplitude) were optimised in relation to the peak current intensity, and a calibration curve was set up in a concentration range of 4.40?×?10?8–2.80?×?10?6 mol L?1, with a detection limit of 2?×?10?9 mol L?1. After calibration curve was plotted, the developed procedure was applied to determine GLY in previously contaminated samples: milk and orange juice, and in a commercial formulation, obtaining recovery values between 98.31% and 103.75%. These results show that the proposed method can be used for GLY quantification in different samples with high sensitivity, specificity, stability, and reproducibility.  相似文献   
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